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exceedances of either limitation identified in 40 CFR Part 434 that is applicable to reclamation areas <br />on coal mines (settleable solids of 0.5 ml /l and pH of 6.0 to 9.0). Peabody Sage Creek Mine only <br />notes settleable solids values that are at or above the detection limit of 0.4 ml /1; no exceedances of 0.4 <br />ml/1 were noted. <br />Impacts to Alluvial Valley Floors (AVFs) <br />The Division determined that there are two potential AVFs in the Grassy Creek basin. They include <br />a 45 -acre partial near the confluence of Little Grassy Creek and Grassy Creek and a 40 -acre parcel <br />along Little Grassy Creek. Per Rule 424.3(4), the Division determined that these two parcels are <br />exempt, and a evaluation was not required. <br />An AVF is present in the Fish Creek basin downstream of Pond 004. This AVF was originally <br />discussed on page 7 -279, Tab 7 of the Seneca II Mine permit and the discussion was inserted into the <br />Peabody Sage Creek Mine permit. There is a 63 acre parcel where irrigation was practiced on this <br />AVF from the point where Cow Camp Creek is confluent with Fish Creek to the confluence of Fish <br />Creek and Trout Creek. However, the irrigation ditch for this parcel washed out in 1997 and has not <br />been used since that date. An impact projection analysis, conducted by the Seneca II Mine as noted <br />in Tab 7, Section VILA. Lc in C- 1980 -005 and included in the Peabody Sage Creek Mine permit, <br />concluded that total dissolved solids (TDS) increase in the Fish Creek stream flow as a result of <br />surface water discharges from NPDES4 on the order of 76 mg /l and 74 mg /l for the months of June <br />and July respectively. The projection equates to TDS concentrations in the Fish Creek streamflow <br />ranging from 497 to 607 mg /1. <br />Based on a demonstration provided in Tab 7, Section VII.B. Lc of the Seneca II Mine permit (C- <br />1980 -005), crops grown in the area of alluvium can tolerate TDS concentrations in excess of 2,000 <br />mg /1. Predicted TDS concentrations of Fish Creek streamflow of only 497 to 607 mg /1 will not result <br />in water quality changes that significantly and adversely affect the composition, diversity or <br />production of the vegetation dependent on subirrigation. Water quality data for June and July at Sites <br />SSF11 and SSF13 from 2003 to 2013 show that the maximum increase of TDS between the sites was <br />50 mg /1 in June (a 74 mg /l increase was predicted) and 70 mg /l in July (a 74 mg /1 increase was <br />predicted). TDS increases on Fish Creek due to the Peabody Sage Creek Mine are not causing <br />significant negative impact to potential crops in the area. <br />Findings on Protection of Hydrolo2ic Balance <br />According to Rule 3.03.2(2), the Division must conduct an inspection and an evaluation to determine <br />whether pollution of surface or subsurface water is occurring, the probability of future occurrence of <br />such pollution, and the estimated cost of abating such pollution. <br />Based on the review of the water monitoring data for the SL -3 Bond release area of the Peabody Sage <br />Creek Mine, the observed hydrological impacts are consistent with those predicted in the probable <br />hydrologic consequences (PHC) section of the permit, C- 2009 -087. Although the 4.6 ug /l selenium <br />standard was exceeded at both NPDES2 and NPDES4, both Pond 002 and 004 associated with these <br />discharges are not included in the areas associated with the SL -3 bond release application. The <br />